I was under the impression my mortgage with the Coventry Building Society was a tracker. Recently, they've reduced their SVR by the full 1.5%, but my mortgage has not changed at all. Apparently it's what they call "managed". It doesn't track the base rate or the SVR, they just set a value for it and guarantee it will never be over their SVR. I really am starting to feel a little cheated, because I was under the impression the mortgage tracked interest rate changes (either base or their SVR). It does not.

What course of action can I take in this instance?

Edit: it's a so called "Flexx" mortgage. Eventually if interest rates keep falling, I'll be paying the SVR!